Power Quality Analysis (PF, THD & Voltage Stability)
Identifying and correcting harmonic distortion, voltage instability, and power factor issues protecting critical systems.
Why Power Quality Matters
Modern electrical systems face power quality challenges that didn't exist a generation ago. Variable speed drives, switched-mode power supplies, LED lighting, and renewable energy sources introduce harmonic distortion, voltage fluctuations, and reactive power issues that degrade equipment performance and shorten lifespan.
Poor power quality manifests as unexplained equipment failures, nuisance tripping, overheating transformers, premature capacitor failure, and increased energy costs. For IT infrastructure, the consequences include server crashes, data corruption, and unplanned downtime.
Our power quality analysis identifies root causes, quantifies problems against industry standards (IEEE 519, EN 50160), and implements corrective engineering to restore clean, stable electrical supply.
Common Power Quality Issues
Harmonic Distortion
Non-sinusoidal waveforms caused by non-linear loads. Creates overheating, neutral conductor overload, and interference with sensitive equipment. Measured as Total Harmonic Distortion (THD).
Voltage Sags & Swells
Temporary voltage reductions or increases caused by load switching, motor starts, or grid events. Resets controls, crashes IT systems, and damages variable speed drives.
Power Factor Issues
Reactive power from motors, transformers, and lighting reduces system capacity and increases bills. Power factor below 0.95 typically attracts supplier penalties.
Transients & Spikes
High-frequency voltage spikes from lightning, switching operations, or equipment faults. Destroys electronics, corrupts data, and causes cascading failures in networked systems.
Power Quality Survey Process
Phase 1: Baseline Monitoring
We install calibrated power quality analysers at critical points throughout the electrical distribution system, typically for 7-14 days to capture daily, weekly, and load variation patterns.
- •Voltage and current waveform recording at 200 samples per cycle
- •Harmonic analysis up to 50th order (2.5kHz) per IEEE 519
- •Power factor, reactive power, and demand profiling
- •Transient capture with sub-cycle time resolution
Phase 2: Data Analysis
Raw data is processed against international standards to identify non-compliances, quantify severity, and correlate issues with operational events or equipment behaviour.
- •IEEE 519 harmonic limits for both voltage and current distortion
- •EN 50160 voltage quality benchmarks for UK commercial supply
- •Equipment compatibility assessment against recorded conditions
- •Financial impact quantification including energy waste and penalties
Phase 3: Corrective Engineering
Based on analysis findings, we design and implement targeted solutions to restore power quality within acceptable limits.
- •Harmonic filters (passive or active) sized for measured distortion levels
- •Power factor correction systems with detuned capacitors
- •Voltage regulation equipment including AVRs or tap-changing transformers
- •Surge protection and transient suppression at sensitive loads
- •Neutral conductor upgrades for high harmonic current installations
Critical Infrastructure Applications
Data Centres: Server power supplies are highly non-linear loads creating significant harmonic currents. Poor power quality causes IT equipment failures, corrupted data, and reduced UPS runtime. We validate that data hall power meets ASHRAE and TIA-942 recommendations.
Manufacturing: Variable speed drives controlling motors, conveyors, and process equipment generate harmonics while simultaneously being sensitive to voltage sags and transients. Power quality issues manifest as production stoppages, scrap, and equipment damage.
Healthcare: Medical imaging equipment (MRI, CT scanners) creates power quality disturbances affecting other sensitive systems. Life-critical equipment requires stable, clean power with appropriate isolation and conditioning.
Commercial Offices: Modern offices with extensive IT infrastructure, LED lighting, and HVAC controls face cumulative power quality degradation. This affects productivity (computer crashes), comfort (lighting flicker), and energy efficiency.
Benefits of Power Quality Improvement
- ✓Reduced unplanned downtime from equipment trips and failures
- ✓Extended equipment lifespan by eliminating thermal stress and voltage strain
- ✓Lower energy costs through improved efficiency and eliminated power factor penalties
- ✓Increased system capacity without infrastructure upgrades
- ✓Reduced insurance risk from electrical incidents and fire hazards
- ✓Compliance with equipment warranty requirements and industry standards
Related Services
Electrical Compliance
Complete electrical testing, inspection, and certification programs.
UPS Maintenance
Uninterruptible power supply servicing and battery management.
Thermal Imaging
Infrared surveys to detect electrical faults and overheating.
Arc Flash Assessment
High-voltage and low-voltage electrical hazard quantification.
Generator Maintenance
Backup power system servicing and power quality validation.
Data Room Audits
Server room and data centre infrastructure compliance checks.
Frequently Asked Questions
Concerned About Power Quality?
Comprehensive surveys identifying harmonics, voltage issues, and power factor problems with corrective engineering solutions.